The present invention relates to a titterboard type switch with overload protection function, and more particularly to a switch with security structure, wherein a bimetallic plate is disposed between an electrothermal conductor and a swinging member. In case of passing of excessively great current, the bimetallic plate is deformed to drive the swinging member to cut off the power so as to protect the electric appliance from being damaged and ensure the safety in using electricity.
Accidents due to improper use of electricity have taken place more and more frequently. Therefore, it is necessary to provide an effective protection measure for ensuring safety in using electricity. The most widely used protection measure is the current limiting device mounted on the main circuit, such as a fuse or interrupter which is able to cut off the power in the case of overload. However, it is necessary to replace the fuse each time after fused. This causes great inconvenience. On the other hand, the interrupter has complicated structure and high price so that it is uneconomic to use the interrupter on each line. Also, it is difficult to mount the interrupter. Therefore, generally the interrupter is made with relatively great current specification, so that several lines of smaller current can commonly use one interrupter so as to save cost and facilitate installation. As a result, the precision of the interrupter can hardly meet the requirements for security of various circuits with different current limitations.